Articles | Volume 22, issue 14
https://doi.org/10.5194/bg-22-3699-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-22-3699-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
30 Jul 2025
Research article |
| 30 Jul 2025
| 30 Jul 2025
Evaluating ocean alkalinity enhancement as a carbon dioxide removal strategy in the North Sea
Institute of Coastal Systems, Helmholtz-Zentrum Hereon, Geesthacht, Germany
Ute Daewel
Institute of Coastal Systems, Helmholtz-Zentrum Hereon, Geesthacht, Germany
Jan Kossack
Institute of Coastal Systems, Helmholtz-Zentrum Hereon, Geesthacht, Germany
Kubilay Timur Demir
Institute of Coastal Systems, Helmholtz-Zentrum Hereon, Geesthacht, Germany
Helmuth Thomas
Institute of Carbon Cycles, Helmholtz-Zentrum Hereon, Geesthacht, Germany
Institute for Chemistry and Biology of the Marine Environment, Carl von Ossietzky University of Oldenburg, Oldenburg, Germany
Corinna Schrum
Institute of Coastal Systems, Helmholtz-Zentrum Hereon, Geesthacht, Germany
Institute of Oceanography, University of Hamburg, Hamburg, Germany
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Short summary
Ocean alkalinity enhancement (OAE) boosts oceanic CO₂ absorption, offering a climate solution. Using a regional model, we examined OAE in the North Sea, revealing that shallow coastal areas achieve higher CO₂ uptake than offshore where alkalinity is more susceptible to deep-ocean loss. Long-term carbon storage is limited, and pH shifts vary by location. Our findings guide OAE deployment to optimize carbon removal while minimizing ecological effects, supporting global climate mitigation efforts.
Ocean alkalinity enhancement (OAE) boosts oceanic CO₂ absorption, offering a climate solution....
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